Engine issue intermittent grrrrr

Afternoon!
Well after a successful first laning outing in my Jim, driving back down the A1 my little ignition lock light started to flutter followed by the engine managment light and a loss or stuttering of power... this was at 65mph ish. I backed off the power as I was on the motorway at Washington where the A194m merges and didn't wanna die before reaching the hard shoulder! When I backed off after a few seconds the lights went out and it was fine on the back roads home to Lumley. Could this be the crank position sensor breaking down under load? Would this make the ignition light flash too? It did this when I first got it and I had it recovered but my pal found a broken earth behind the engine which we thought it was and it's been fine since but, this is the first prolonged motorway driving it's done.
Any advice is appreciated as it's my daily for work at present and can't afford to be broken down lol

Yes sounds very much like crank position sensor. I presume its the M13 (DOHC) engine?

Yes it's the first of them and it's a right problem for my motor factors to find the part number!!! Any help?

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